They should make Smoker and Tashigi join up (and Aokiji, but that would be overkill).
Would be funny to see Zorro sweat around her.

That would most definitely not happen, 'cause they are just on the grand line because they want to catch the strawhats (they weren't even able to get them when ruffy was just 30 million worth of a pirate, I don't think the both of them would be able to stop the crew for more than a minute now, because Tashigi isn't that much of a deal, smoker could be troublesome without an elemental fruituser on board, but they could deal with him). To sum it up, that won't happen, at least I think so.

But it would be funny if they did. Mostly because the cool Zorro gets so worked up (him hiding behind some barrels in Alabasta because of her was so funny).

Just like it would've been funny to see how Pauly acted around the frivolous Nami if he had joined up.

And they will be strong when they meet again (just like Buggy will be stronger if he ever shows up again). Smoker already is strong but Tashgi will be also.
I mean if Coby can use Soru now and be strong (he was a bigger wimp than Usopp and would kick his ass now), even Tashgi could be a challenge for Zorro in the future.

"For Feanor was made the mightiest in all parts of body and mind, in valour, in endurance, in beauty, in understanding, in skill, in strength and subtlety alike, of all the Children of Illuvatar, and a bright flame was in him"